McLaren 570 GT4 before/after ECU tune - 640 rwhp

The GT4 version of the McLaren 570 is obviously built for the roadcourse. It gets carbon fiber body panels, revised aerodynamics, stiffer suspension, cooling upgrades, magnesium wheels, etc. It also does not have to meet the same emissions regulations as the street car.

DME Tuning picked up 132 horsepower at the wheels on this Mustang dyno with a Stage 2 97 octane setup but oddly the baseline is much higher and so is the peak power output. It seems to be corrected to read like a Dynojet if not higher.

Regardless, 570 GT4 race cars are picking up massive gains with just a tune: